Imaging lens

ABSTRACT

There is provided an imaging lens with excellent optical characteristics which satisfies demand of a low profile and a low F-number. An imaging lens comprises in order from an object side to an image side, a first lens with negative refractive power having an object-side surface being convex in a paraxial region, a second lens with positive refractive power in a paraxial region, a third lens with the negative refractive power in a paraxial region, a fourth lens with the positive refractive power in a paraxial region, a fifth lens having a flat object-side surface and a flat image-side surface that are aspheric, and a sixth lens with the negative refractive power having an image-side surface being concave in a paraxial region.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an imaging lens which forms an image ofan object on a solid-state image sensor such as a CCD sensor or a C-MOSsensor used in an imaging device.

Description of the Related Art

In recent years, it becomes common that camera function is mounted invarious products, such as information terminal equipment, homeappliances, automobiles, and the like. Development of products with thecamera function will be made accordingly.

The imaging lens mounted in such equipment is required to be compact andto have high-resolution performance.

As a conventional imaging lens aiming high performance, for example, theimaging lens disclosed in the following Patent Document 1 has beenknown.

Patent Document 1 (CN106526803A) discloses an imaging lens comprising,in order from an object side, a first lens with positive refractivepower having a concave image-side surface, a second lens with negativerefractive power having a concave image-side surface, a third lens withpositive refractive power having a convex image-side surface, a fourthlens with negative refractive power having concave surfaces on bothsides, a fifth lens with positive refractive power having a concaveobject-side surface and a convex image-side surface, and a sixth lenswith negative refractive power having a concave image-side surface.

SUMMARY OF THE INVENTION

However, in lens configurations disclosed in the Patent Document 1, whena low profile and a low F-number are to be realized, it is verydifficult to correct aberrations at a peripheral area, and excellentoptical performance can not be obtained.

The present invention has been made in view of the above-describedproblems, and an object of the present invention is to provide animaging lens with high resolution which satisfies demand of the lowprofile and the low F-number in well balance and excellently correctsaberrations.

Regarding terms used in the present invention, “a convex surface (asurface being convex)”, “a concave surface (a surface being concave)” or“a flat surface (a surface being flat)” of lens surfaces implies a shapeof the lens surface in a paraxial region (near the optical axis).“Refractive power” implies the refractive power in a paraxial region. “Apole point” implies an off-axial point on an aspheric surface at which atangential plane intersects the optical axis perpendicularly. “A totaltrack length” is defined as a distance along the optical axis from anobject-side surface of an optical element located closest to the objectto an image plane. “The total track length” and “a back focus” is adistance obtained when thickness of an IR cut filter or a cover glasswhich may be arranged between the imaging lens and the image plane isconverted into an air-converted distance.

An imaging lens according to the present invention comprises, in orderfrom an object side to an image side, a first lens with negativerefractive power having an object-side surface being convex in aparaxial region, a second lens with positive refractive power in aparaxial region, a third lens with the negative refractive power in aparaxial region, a fourth lens with the positive refractive power in aparaxial region, a fifth lens having a flat object-side surface and aflat image-side surface that are aspheric, and a sixth lens with thenegative refractive power having an image-side surface being concave ina paraxial region.

According to the imaging lens having an above-described configuration,the first lens achieves a wide field of view by strengthening therefractive power, and coma aberration, astigmatism and distortion areproperly corrected. Furthermore, when the first lens has the object-sidesurface being convex in the paraxial region, spherical aberration andthe distortion are properly corrected.

The second lens achieves reduction in a profile, and properly correctsthe astigmatism and the distortion.

The third lens properly corrects chromatic aberration, the sphericalaberration, the astigmatism and the distortion.

The fourth lens achieves reduction in the profile, and properly correctsthe astigmatism and the distortion.

When the fifth lens has the flat object-side surface and the flatimage-side surface in the paraxial region, the astigmatism, fieldcurvature and the distortion are properly corrected by aspheric surfacesformed on both sides without affecting a focal length of the overalloptical system of the imaging lens.

The sixth lens properly corrects the chromatic aberration, theastigmatism, the distortion and the field curvature. Furthermore, whenthe sixth lens has the image-side surface being concave in the paraxialregion, a back focus can be secured while maintaining the low profile.

According to the imaging lens having the above-described configuration,it is preferable that the first lens has an image-side surface beingconcave in the paraxial region.

When the first lens has the image-side surface being concave in theparaxial region, the coma aberration, the astigmatism and the distortioncan be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the second lens has an image-side surface beingconvex in the paraxial region.

When the second lens has the image-side surface being convex in theparaxial region, a light ray incident angle to the image-side surface ofthe second lens can be appropriately controlled, and the astigmatism canbe properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the third lens has an image-side surface beingconcave in the paraxial region.

When the third lens has the image-side surface being concave in theparaxial region, the astigmatism and the distortion can be properlycorrected.

According to the imaging lens having the above-described configuration,it is preferable that the fourth lens has an image-side surface beingconvex in the paraxial region.

When the fourth lens has the image-side surface being convex in theparaxial region, a light ray incident angle to the image-side surface ofthe fourth lens can be appropriately controlled, and the astigmatism andthe distortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the sixth lens has the image-side surface formedas an aspheric surface having at least one pole point in a position offthe optical axis.

When the sixth lens has the image-side surface formed as the asphericsurface having at least one pole point in a position off the opticalaxis, the field curvature and the distortion are properly corrected, anda light ray incident angle to an image sensor is appropriatelycontrolled.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (1) issatisfied:

−9.55<(T1/f1)×100<−1.00  (1)

where

T1: a distance along the optical axis from an image-side surface of thefirst lens to an object-side surface of the second lens, and

f1: a focal length of the first lens.

The conditional expression (1) defines an appropriate range of arelationship between the distance along the optical axis from theimage-side surface of the first lens to the object-side surface of thesecond lens, and the focal length of the first lens. When a value isbelow the upper limit of the conditional expression (1), the distancealong the optical axis from the image-side surface of the first lens tothe object-side surface of the second lens is prevented from being toosmall, and a light ray incident angle to the object-side surface of thesecond lens is appropriately controlled. Furthermore, the refractivepower of the first lens is prevented from being too small, and thechromatic aberration can be properly corrected. On the other hand, whenthe value is above the lower limit of the conditional expression (1),the distance along the optical axis from the image-side surface of thefirst lens to the object-side surface of the second lens is preventedfrom being too large, and the refractive power of the first lens isprevented from being too large, and reduction in the profile isachieved.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (2) issatisfied:

0.02<T2/T3<0.60  (2)

where

T2: a distance along the optical axis from an image-side surface of thesecond lens to an object-side surface of the third lens, and

T3: a distance along the optical axis from an image-side surface of thethird lens to an object-side surface of the fourth lens.

The conditional expression (2) defines an appropriate range of arelationship between the distance along the optical axis from theimage-side surface of the second lens to the object-side surface of thethird lens, and the distance along the optical axis from the image-sidesurface of the third lens to the object-side surface of the fourth lens.By satisfying the conditional expression (2), the third lens is arrangedat an optimum position, and aberration correction function of the lensbecomes more effective. As a result, reduction in the profile can beachieved, and the astigmatism and the distortion can be properlycorrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (3) issatisfied:

−15.50<f6/D6<−1.50  (3)

where

f6: a focal length of the sixth lens, and

D6: a thickness along the optical axis of the sixth lens.

The conditional expression (3) defines an appropriate range of arelationship between the focal length of the sixth lens, and thethickness along the optical axis of the sixth lens. When a value isbelow the upper limit of the conditional expression (3), refractivepower of the sixth lens is prevented from being too large, and theastigmatism, the field curvature and the distortion can be properlycorrected. Furthermore, the thickness along the optical axis of thesixth lens is prevented from being too large, and reduction in theprofile can be achieved. On the other hand, when the value is above thelower limit of the conditional expression (3), the refractive power ofthe sixth lens is prevented from being too small, and the chromaticaberration can be properly corrected. Furthermore, the thickness alongthe optical axis of the sixth lens is prevented from being too small,and the formability of the lens is improved.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (4) issatisfied:

−2.45<r2/r4<−0.45  (4)

where

r2: a paraxial curvature radius of an image-side surface of the firstlens, and

r4: a paraxial curvature radius of an image-side surface of the secondlens.

The conditional expression (4) defines an appropriate range of arelationship between the paraxial curvature radius of the image-sidesurface of the first lens and the paraxial curvature radius of theimage-side surface of the second lens. By satisfying the conditionalexpression (4), refractive powers of the image-side surface of the firstlens and the image-side surface of the second lens are suppressed frombeing excessive. As a result, reduction in the profile can be achieved,and the astigmatism and the distortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (5) issatisfied:

0.65<r1/f<4.00  (5)

where

r1: a paraxial curvature radius of an object-side surface of the firstlens, and

f: a focal length of the overall optical system of the imaging lens.

The conditional expression (5) defines an appropriate range of theparaxial curvature radius of the object-side surface of the first lens.When a value is below the upper limit of the conditional expression (5),the coma aberration and the astigmatism can be properly corrected.Furthermore, the thickness along the optical axis of the sixth lens isprevented from being too large, and reduction in the profile isachieved. On the other hand, when the value is above the lower limit ofthe conditional expression (5), the spherical aberration and thedistortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (6) issatisfied:

0.80<r12/D6<3.00  (6)

where

r12: a paraxial curvature radius of an image-side surface of the sixthlens, and

D6: a thickness along the optical axis of the sixth lens.

The conditional expression (6) defines an appropriate range of arelationship between the paraxial curvature radius of the image-sidesurface of the sixth lens and the thickness along the optical axis ofthe sixth lens. By satisfying the conditional expression (6), refractivepower of the image-side surface of the sixth lens can be maintained, andthe thickness along the optical axis of the sixth lens can be secured.As a result, the astigmatism, the field curvature and the distortion canbe suppressed, and the formability of the sixth lens is improved.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (7) issatisfied:

14.00<νd6<36.00  (7)

where

νd6: an abbe number at d-ray of the sixth lens.

The conditional expression (7) defines an appropriate range of the abbenumber at d-ray of the sixth lens. By satisfying the conditionalexpression (7), the chromatic aberration can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (8) issatisfied:

−10.00<(D1/f1)×100<−1.00  (8)

where

D1: a thickness along the optical axis of the first lens, and

f1: a focal length of the first lens.

The conditional expression (8) defines an appropriate range of arelationship between the thickness along the optical axis of the firstlens and the focal length of the first lens. When a value is below theupper limit of the conditional expression (8), the thickness along theoptical axis of the first lens is prevented from being too small, andthe formability of the lens is improved. Furthermore, refractive powerof the first lens is prevented from being too small, and the chromaticaberration can be properly corrected. On the other hand, when the valueis above the lower limit of the conditional expression (8), thethickness along the optical axis of the first lens is prevented frombeing too large, and reduction in the profile can be achieved.Furthermore, refractive power of the first lens is prevented from beingtoo large, and the coma aberration, the astigmatism and the distortioncan be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (9) issatisfied:

0.90<D2/D3<4.70  (9)

where

D2: a thickness along the optical axis of the second lens, and

D3: a thickness along the optical axis of the third lens.

The conditional expression (9) defines an appropriate range of arelationship between the thickness along the optical axis of the secondlens and the thickness along the optical axis of the third lens. Bysatisfying the conditional expression (9), the thicknesses along theoptical axis of the second lens and the third lens can be appropriatelybalanced. As a result, reduction in the profile is achieved, and theformability of the second lens and the third lens is improved. Inaddition, by satisfying the conditional expression (9), the astigmatismand the distortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (10) issatisfied:

0.30<f4/f<1.70  (10)

where

f4: a focal length of the fourth lens, and

f: a focal length of the overall optical system of the imaging lens.

The conditional expression (10) defines an appropriate range ofrefractive power of the fourth lens. When a value is below the upperlimit of the conditional expression (10), the positive refractive powerof the fourth lens becomes appropriate, and reduction in the profile canbe achieved. On the other hand, when the value is above the lower limitof the conditional expression (10), the spherical aberration, theastigmatism and the distortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (11) issatisfied:

−10.00<f1/f4<−0.80  (11)

where

f1: a focal length of the first lens, and

f4: a focal length of the fourth lens.

The conditional expression (11) defines an appropriate range of arelationship between the focal length of the first lens and the focallength of the fourth lens. By satisfying the conditional expression(11), refractive powers of the first lens and the fourth lens can beappropriately balanced. As a result, reduction in the profile can beachieved, and the chromatic aberration, the coma aberration, theastigmatism and the distortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (12) issatisfied:

0.40<f1/f6<9.00  (12)

where

f1: a focal length of the first lens, and

f6: a focal length of the sixth lens.

The conditional expression (12) defines an appropriate range of arelationship between the focal length of the first lens and the focallength of the sixth lens. By satisfying the conditional expression (12),refractive powers of the first lens and the sixth lens can beappropriately balanced. As a result, the chromatic aberration, the comaaberration, the astigmatism, the field curvature and the distortion canbe properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (13) issatisfied:

|r3|/r4<−1.50  (13)

where

r3: a paraxial curvature radius of an object-side surface of the secondlens, and

r4: a paraxial curvature radius of an image-side surface of the secondlens, and

The conditional expression (13) defines an appropriate range of arelationship between the paraxial curvature radius of the object-sidesurface of the second lens and the paraxial curvature radius of theimage-side surface of the second lens. By satisfying the conditionalexpression (13), refractive powers of the object-side surface of thesecond lens and the image-side surface of the second lens can beappropriately balanced. As a result, the astigmatism and the distortioncan be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (14) issatisfied:

−1.10<r2/r4/r6<−0.10  (14)

where

r2: a paraxial curvature radius of an image-side surface of the firstlens,

r4: a paraxial curvature radius of an image-side surface of the secondlens, and

r6: a paraxial curvature radius of an image-side surface of the thirdlens.

The conditional expression (14) defines an appropriate range of arelationship among the paraxial curvature radius of the image-sidesurface of the first lens, the paraxial curvature radius of theimage-side surface of the second lens, and the paraxial curvature radiusof the image-side surface of the third lens. By satisfying theconditional expression (14), refractive powers of the image-sidesurfaces of the first lens, the second lens and the third lens,respectively can be appropriately balanced. As a result, the comaaberration, the astigmatism and the distortion can be properlycorrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (15) issatisfied:

30.00<r2/T2  (15)

where

r2: a paraxial curvature radius of an image-side surface of the firstlens, and

T2: a distance along the optical axis from an image-side surface of thesecond lens to an object-side surface of the third lens.

The conditional expression (15) defines an appropriate range of arelationship between the paraxial curvature radius of the image-sidesurface of the first lens and the distance along the optical axis fromthe image-side surface of the second lens to the object-side surface ofthe third lens. By satisfying the conditional expression (15), the widefield of view can be achieved, a light ray incident angle to theobject-side surface of the second lens can be appropriately controlled,and the astigmatism and the distortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (16) issatisfied:

−0.90<r4/f<−0.20  (16)

where

r4: a paraxial curvature radius of an image-side surface of the secondlens, and

f: a focal length of the overall optical system of the imaging lens.

The conditional expression (16) defines an appropriate range of theparaxial curvature radius of the image-side surface of the second lens.When a value is below the upper limit of the conditional expression(16), the spherical aberration and the distortion can be properlycorrected. On the other hand, when the value is above the lower limit ofthe conditional expression (16), the astigmatism can be properlycorrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (17) issatisfied:

0.90<|r7|/f<20.00  (17)

where

r7: a paraxial curvature radius of an object-side surface of the fourthlens, and

f: a focal length of the overall optical system of the imaging lens.

The conditional expression (17) defines an appropriate range of theparaxial curvature radius of the object-side surface of the fourth lens.By satisfying the conditional expression (17), the astigmatism and thedistortion can be properly corrected.

According to the imaging lens having the above-described configuration,it is preferable that the following conditional expression (18) issatisfied:

−0.80<r8/f<−0.15  (18)

where

r8: a paraxial curvature radius of an image-side surface of the fourthlens, and

f: a focal length of the overall optical system of the imaging lens.

The conditional expression (18) defines an appropriate range of theparaxial curvature radius of the image-side surface of the fourth lens.By satisfying the conditional expression (18), the astigmatism and thedistortion can be properly corrected.

Effect of Invention

According to the present invention, there can be provided an imaginglens with high resolution which satisfies demand of the low profile andthe low F-number in well balance, and properly corrects aberrations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing an imaging lens in Example 1according to the present invention.

FIG. 2 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 1 according to the present invention.

FIG. 3 is a schematic view showing an imaging lens in Example 2according to the present invention.

FIG. 4 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 2 according to the present invention.

FIG. 5 is a schematic view showing an imaging lens in Example 3according to the present invention.

FIG. 6 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 3 according to the present invention.

FIG. 7 is a schematic view showing an imaging lens in Example 4according to the present invention.

FIG. 8 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 4 according to the present invention.

FIG. 9 is a schematic view showing an imaging lens in Example 5according to the present invention.

FIG. 10 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 5 according to the present invention.

FIG. 11 is a schematic view showing an imaging lens in Example 6according to the present invention.

FIG. 12 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 6 according to the present invention.

FIG. 13 is a schematic view showing an imaging lens in Example 7according to the present invention.

FIG. 14 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 7 according to the present invention.

FIG. 15 is a schematic view showing an imaging lens in Example 8according to the present invention.

FIG. 16 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 8 according to the present invention.

FIG. 17 is a schematic view showing an imaging lens in Example 9according to the present invention.

FIG. 18 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 9 according to the present invention.

FIG. 19 is a schematic view showing an imaging lens in Example 10according to the present invention.

FIG. 20 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 10 according to the present invention.

FIG. 21 is a schematic view showing an imaging lens in Example 11according to the present invention.

FIG. 22 shows spherical aberration, astigmatism, and distortion of theimaging lens in Example 11 according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, the preferred embodiment of the present invention will bedescribed in detail referring to the accompanying drawings.

FIGS. 1, 3, 5, 7, 9, 11, 13, 15, 17, 19 and 21 are schematic views ofthe imaging lenses in Examples 1 to 11 according to the embodiments ofthe present invention, respectively.

The imaging lens according to the present invention comprises, in orderfrom an object side to an image side, a first lens L1 with negativerefractive power having an object-side surface being convex in aparaxial region, a second lens L2 with positive refractive power in aparaxial region, a third lens L3 with the negative refractive power in aparaxial region, a fourth lens L4 with the positive refractive power ina paraxial region, a fifth lens L5 having a flat object-side surface anda flat image-side surface that are aspheric, and a sixth lens L6 withthe negative refractive power having an image-side surface being concavein a paraxial region.

A filter IR such as an IR cut filter or a cover glass is arrangedbetween the sixth lens L6 and an image plane IMG (namely, the imageplane of an image sensor). The filter IR is omissible.

An aperture stop ST is arranged between the first lens L1 and the secondlens L2, and correction of aberrations and control of an incident angleof a light ray of high image height to an image sensor becomefacilitated.

The first lens L1 has the negative refractive power and is formed in ameniscus shape having the object-side surface being convex and animage-side surface being concave in a paraxial region (near the opticalaxis X). Therefore, a wide field of view is achieved, and sphericalaberration, coma aberration, astigmatism and distortion are properlycorrected.

The second lens L2 has the positive refractive power and is formed in abiconvex shape having an object-side surface and an image-side surfacebeing both convex in the paraxial region. Therefore, reduction in theprofile is achieved, and the astigmatism and the distortion are properlycorrected.

The second lens L2 may be formed in a meniscus shape having theobject-side surface being concave and the image-side surface beingconvex in the paraxial region (near the optical axis X) as in theExample 8 shown in FIG. 15. In this case, a light ray incident angle tothe second lens L2 can be appropriately controlled, and the distortioncan be properly corrected.

The third lens L3 has the negative refractive power and is formed in ameniscus shape having the object-side surface being convex and animage-side surface being concave in a paraxial region (near the opticalaxis X). Therefore, the chromatic aberration, the spherical aberration,the astigmatism and the distortion are properly corrected.

The third lens L3 may be formed in a biconcave shape having theobject-side surface and the image-side surface being both concave in theparaxial region as in the Examples 10 and 11 shown in FIGS. 19 and 21.This case is favorable for correcting the chromatic aberration due tothe negative refractive powers on both sides.

The fourth lens L4 has the positive refractive power and is formed in ameniscus shape having an object-side surface being concave and animage-side surface being convex in a paraxial region (near the opticalaxis X). Therefore, reduction in a profile is achieved, and theastigmatism and the distortion are properly corrected.

The fourth lens L4 may be formed in the biconvex shape having theobject-side surface and the image-side surface being both convex in theparaxial region as in the Examples 7, 8 and 9 shown in FIGS. 13, 15 and17. This case is favorable for reduction in the profile due to thepositive refractive powers on both sides.

The fifth lens L5 substantially has no refractive power, and is formedin a shape having an object-side surface and an image-side surface thatare flat in a paraxial region (near the optical axis X). Therefore, theastigmatism, the field curvature and the distortion are properlycorrected by aspheric surfaces formed on both sides without affecting afocal length of the overall optical system of the imaging lens.

The sixth lens L6 has the negative refractive power and is formed in ameniscus shape having an object-side surface being convex and theimage-side surface being concave in the paraxial region. Therefore, thechromatic aberration, the astigmatism, the distortion and the fieldcurvature are properly corrected while securing a back focus.

The sixth lens L6 may be formed in a shape having the object-sidesurface being flat and the image-side surface being concave in theparaxial region as in the Examples 2, 4 and 5 shown in FIGS. 3, 7 and 9.In this case, the object-side surface is formed as an aspheric surfaceand properly corrects aberrations at a peripheral area.

The image-side surface of the sixth lens L6 is formed as the asphericsurface having at least one pole point in the position off the opticalaxis. Therefore, the field curvature and the distortion are moreproperly corrected and a light ray incident angle to the image sensorcan be appropriately controlled.

Regarding the imaging lens according to the present embodiments, it ispreferable that all lenses of the first lens L1 to the sixth lens L6 aresingle lenses. Configuration only with the single lenses can frequentlyuse the aspheric surfaces. In the present embodiments, all lens surfacesare formed as appropriate aspheric surfaces, and the aberrations arefavorably corrected. Furthermore, in comparison with a case in which acemented lens is used, workload is reduced, and manufacturing in lowcost becomes possible.

Furthermore, the imaging lens according to the present embodiments makesmanufacturing facilitated by using a plastic material for the lenses,and mass production in a low cost can be realized.

The material applied to the lens is not limited to the plastic material.By using glass material, further high performance may be aimed. It ispreferable that all of lens-surfaces are formed as aspheric surfaces,however, spherical surfaces easy to be manufactured may be adopted inaccordance with required performance.

The imaging lens according to the present embodiments shows preferableeffect by satisfying the following conditional expressions (1) to (18).

−9.55<(T1/f1)×100<−1.00  (1)

0.02<T2/T3<0.60  (2)

−15.50<f6/D6<−1.50  (3)

−2.45<r2/r4<−0.45  (4)

0.65<r1/f<4.00  (5)

0.80<r12/D6<3.00  (6)

14.00<νd6<36.00  (7)

−10.00<(D1/f1)×100<−1.00  (8)

0.90<D2/D3<4.70  (9)

0.30<f4/f<1.70  (10)

−10.00<f1/f4<−0.80  (11)

0.40<f1/f6<9.00  (12)

|r3|/r4<−1.50  (13)

−1.10<r2/r4/r6<−0.10  (14)

30.00<r2/T2  (15)

−0.90<r4/f<−0.20  (16)

0.90<|r7|/f<20.00  (17)

−0.80<r8/f<−0.15  (18)

where

νd6: an abbe number at d-ray of the sixth lens L6,

D1: a thickness along the optical axis X of the first lens L1,

D2: a thickness along the optical axis X of the second lens L2,

D3: a thickness along the optical axis X of the third lens L3,

D6: a thickness along the optical axis X of the sixth lens L6,

T1: a distance along the optical axis X from an image-side surface ofthe first lens L1 to an object-side surface of the second lens L2,

T2: a distance along the optical axis X from an image-side surface ofthe second lens L2 to an object-side surface of the third lens L3,

T3: a distance along the optical axis X from an image-side surface ofthe third lens L3 to an object-side surface of the fourth lens L4,

f: a focal length of the overall optical system of the imaging lens,

f1: a focal length of the first lens L1,

f4: a focal length of the fourth lens L4,

f6: a focal length of the sixth lens L6,

r1: a paraxial curvature radius of an object-side surface of the firstlens L1,

r2: a paraxial curvature radius of an image-side surface of the firstlens L1,

r3: a paraxial curvature radius of an object-side surface of the secondlens L2,

r4: a paraxial curvature radius of an image-side surface of the secondlens L2,

r6: a paraxial curvature radius of an image-side surface of the thirdlens L3,

r7: a paraxial curvature radius of an object-side surface of the fourthlens L4,

r8: a paraxial curvature radius of an image-side surface of the fourthlens L4, and

r12: a paraxial curvature radius of an image-side surface of the sixthlens L6.

It is not necessary to satisfy the above all conditional expressions,and by satisfying the conditional expression individually, operationaladvantage corresponding to each conditional expression can be obtained.

The imaging lens according to the present embodiments shows furtherpreferable effect by satisfying the below conditional expressions (1a)to (18a).

−8.75<(T1/f1)×100<−1.70  (1a)

0.03<T2/T3<0.50  (2a)

−14.00<f6/D6<−2.50  (3a)

−2.15<r2/r4<−0.75  (4a)

0.95<r1/f<3.50  (5a)

1.20<r12/D6<2.75  (6a)

19.00<νd6<31.00  (7a)

−8.50<(D1/f1)×100<−1.70  (8a)

1.40<D2/D3<4.15  (9a)

0.50<f4/f<1.45  (10a)

−8.50<f1/f4<−1.30  (11a)

0.60<f1/f6<7.50  (12a)

−2000.00<|r3|/r4<−2.00  (13a)

−0.95<r2/r4/r6<−0.20  (14a)

36.00<r2/T2<220.00  (15a)

−0.80<r4/f<−0.35  (16a)

1.05<|r7|/f<16.50  (17a)

−0.70<r8/f<−0.20  (18a)

The signs in the above conditional expressions have the same meanings asthose in the paragraph before the preceding paragraph.

In this embodiment, the aspheric shapes of the aspheric surfaces of thelens are expressed by Equation 1, where Z denotes an axis in the opticalaxis direction, H denotes a height perpendicular to the optical axis, Rdenotes a paraxial curvature radius, k denotes a conic constant, and A4,A6, A8, A10, A12, A14, A16, A18 and A20 denote aspheric surfacecoefficients.

$\begin{matrix}{Z = {\frac{\frac{H^{2}}{R}}{1 + \sqrt{1 - {\left( {k + 1} \right)\frac{H^{2}}{R^{2}}}}} + {A_{4}H^{4}} + {A_{6}H^{6}} + {A_{8}H^{8}} + {A_{10}H^{10}} + {A_{12}H^{12}} + {A_{14}H^{14}} + {A_{16}H^{16}} + {A_{18}H^{18}} + {A_{20}H^{20}}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

Next, examples of the imaging lens according to this embodiment will beexplained. In each example, f denotes a focal length of the overalloptical system of the imaging lens, Fno denotes an F-number, w denotes ahalf field of view, ih denotes a maximum image height, and TTL denotes atotal track length. Additionally, i denotes a surface number countedfrom the object side, r denotes a paraxial curvature radius, d denotes adistance of lenses along the optical axis (surface distance), Nd denotesa refractive index at d-ray (reference wavelength), and νd denotes anabbe number at d-ray. As for aspheric surfaces, an asterisk (*) is addedafter surface number i.

Example 1

The basic lens data is shown below in Table 1.

TABLE 1 Example 1 Unit mm f = 3.12 Fno = 2.20 ω(°) = 54.2 h = 3.69 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 10.23530.3275 1.535 55.69 (νd1)  2* 3.6473 0.4406  3 (Stop) Infinity −0.0159 4* 5.3142 0.6582 1.544 56.44 (νd2)  5* −2.0154 0.0250  6* 7.9402 0.30001.671 19.24 (νd3)  7* 4.2063 0.3461  8* −3.9091 1.5399 1.535 55.69 (νd4) 9* −1.1129 0.0200 10* Infinity 0.4800 1.671 19.24 (νd5) 11* Infinity0.2074 12* 52.8029 0.5950 1.639 23.52 (νd6) 13* 1.4084 0.6000 14Infinity 0.2100 1.517 64.20 15 Infinity 0.3660 Image Infinity PlaneConstituent Lens Data Lens Start Surface Focal Length 1 1 −10.782 2 42.772 3 6 −13.780 4 8 2.441 5 10 Infinity 6 12 −2.274 Aspheric SurfaceData First Second Fourth Fifth Sixth Seventh Surface Surface SurfaceSurface Surface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 3.352432E+00  0.000000E+00  0.000000E+00 A4 2.325862E−01 3.623732E−014.255530E−02  2.727508E−02 −4.321598E−02 −2.631253E−02 A6 −2.513251E−01 4.834690E−01 1.685821E−01 −8.085160E−02 −2.004599E−01 −8.695072E−02 A85.574211E−01 −6.726708E+00  −2.420891E+00  −2.486008E−01  1.245619E+00 6.359088E−01 A10 −1.013013E+00  4.096610E+01 1.514657E+01  3.566336E+00−3.816831E+00 −2.271959E+00 A12 1.168958E+00 −1.419207E+02 −5.967941E+01  −1.418810E+01  6.710570E+00  5.339424E+00 A14−8.018291E−01  2.960142E+02 1.458621E+02  2.716480E+01 −6.859220E+00−7.868807E+00 A16 2.778602E−01 −3.643902E+02  −2.206580E+02 −2.817735E+01  3.217351E+00  6.957355E+00 A18 −3.591368E−02 2.411476E+02 1.887798E+02  1.519842E+01  1.353103E−01 −3.388052E+00 A200.000000E+00 −6.589510E+01  −7.051571E+01  −3.323277E+00 −4.431477E−01 7.048022E−01 Eighth Ninth Tenth Eleventh Twelfth Thirteenth SurfaceSurface Surface Surface Surface Surface k 6.459315E+00 −2.161948E+00−1.000000E+00  −1.000000E+00 0.000000E+00 −1.999515E+00 A4 2.191976E−02 8.631297E−02 1.072455E−01  1.014908E−01 1.606620E−03 −1.933624E−01 A61.846987E−01 −3.566491E−01 −2.393029E−01  −8.507572E−02 −1.709663E−01  9.178584E−02 A8 −1.126066E+00   5.894754E−01 3.349210E−01  5.880160E−031.657906E−01 −2.856878E−02 A10 3.548046E+00 −6.434634E−01 −3.791901E−01  1.703467E−02 −7.560831E−02   6.206038E−03 A12 −7.049203E+00  4.439033E−01 2.717923E−01 −9.021905E−03 2.019699E−02 −9.575844E−04 A148.880110E+00 −1.856635E−01 −1.224967E−01   2.218628E−03 −3.352310E−03  1.029937E−04 A16 −6.803972E+00   4.262029E−02 3.333358E−02−3.009690E−04 3.422422E−04 −7.342835E−06 A18 2.896992E+00 −3.966757E−034.907366E−03  2.179721E−05 −1.976054E−05   3.104657E−07 A20−5.284937E−01   4.000000E−05 2.958057E−04 −6.629573E−07 4.950699E−07−5.819162E−09

The imaging lens in Example 1 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 2 shows spherical aberration (mm), astigmatism (mm), and distortion(%) of the imaging lens in Example 1. The spherical aberration diagramshows the amount of aberration at each wavelength of F-ray (486 nm),d-ray (588 nm), and C-ray (656 nm). The astigmatism diagram shows theamount of aberration at d-ray on a sagittal image surface S (solid line)and the amount of aberration at d-ray on tangential image surface T(broken line), respectively (same as FIGS. 4, 6, 8, 10, 12, 14, 16, 18,20 and 22). As shown in FIG. 2, each aberration is correctedexcellently.

Example 2

The basic lens data is shown below in Table 2.

TABLE 2 Example 2 Unit mm f = 3.12 Fno = 2.20 ω(°) = 53.9 h = 3.69 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 7.85100.3275 1.535 55.69 (νd1)  2* 3.2018 0.4457  3 (Stop) Infinity −0.0087 4* 6.3718 0.6250 1.544 56.44 (νd2)  5* −1.8016 0.0250  6* 7.1980 0.30001.671 19.24 (νd3)  7* 3.6626 0.3576  8* −3.8709 1.5400 1.535 55.69 (νd4) 9* −1.1160 0.0200 10* Infinity 0.4850 1.671 19.24 (νd5) 11* Infinity0.2227 12* Infinity 0.5950 1.639 23.52 (νd6) 13* 1.4622 0.6000 14Infinity 0.2100 1.517 64.20 15 Infinity 0.3549 Image Infinity PlaneConstituent Lens Data Lens Start Surface Focal Length 1 1 −10.364 2 42.651 3 6 −11.510 4 8 2.454 5 10 Infinity 6 12 −2.288 Aspheric SurfaceData First Second Fourth Fifth Sixth Seventh Surface Surface SurfaceSurface Surface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 2.473573E+00  0.000000E+00  0.000000E+00 A4 2.109559E−01 4.153751E−013.074407E−02  4.041213E−02 −3.722932E−02 −5.008506E−03 A6 −9.996069E−02 −5.307388E−01  1.738292E−01 −9.343469E−02 −1.692019E−01 −2.926844E−01 A83.197735E−02 3.999971E+00 −2.426969E+00  −2.260110E−01  7.633633E−01 1.536549E+00 A10 4.880749E−02 −2.051096E+01  1.513127E+01  3.595489E+00−1.476089E+00 −4.611298E+00 A12 −6.589971E−02  6.966191E+01−5.938473E+01  −1.411085E+01  8.047677E−01  8.983680E+00 A141.306139E−02 −1.496420E+02  1.459166E+02  2.714450E+01  2.035010E+00−1.117778E+01 A16 0.000000E+00 1.997098E+02 −2.208024E+02  −2.825823E+01−4.591255E+00  8.541977E+00 A18 0.000000E+00 −1.522685E+02  1.864242E+02 1.492937E+01  3.715795E+00 −3.669728E+00 A20 0.000000E+00 5.011105E+01−6.700158E+01  −2.982966E+00 −1.088551E+00  6.844890E−01 Eighth NinthTenth Eleventh Twelfth Thirteenth Surface Surface Surface SurfaceSurface Surface k 4.527758E+00 −2.205091E+00 −1.000000E+00 −1.000000E+00−1.000000E+00 −2.023880E+00 A4 9.668611E−02  8.548945E−03  3.217041E−02 3.737819E−02 −3.325624E−02 −1.944026E−01 A6 −4.633080E−01 −1.345910E−01 −1.091984E−01 −1.435689E−02 −9.159388E−02  1.086581E−01 A82.027464E+00  2.698446E−01  2.622850E−01 −5.346930E−03  9.535486E−02−4.571624E−02 A10 −5.376142E+00  −3.552437E−01 −4.139450E−01−8.090790E−04 −4.229972E−02  1.380227E−02 A12 8.577275E+00  2.741682E−01 3.616446E−01  2.743274E−03  1.076470E−02 −2.829624E−03 A14−8.323212E+00  −1.204685E−01 −1.888377E−01 −1.111915E−03  −1.686329E −03 3.798677E−04 A16 4.788903E+00  2.668885E−02  5.764007E−02  2.067049E−04 1.615808E−04 −3.192022E−05 A18 −1.476156E+00  −1.652235E−03−9.350407E−03 −1.904782E−05 −8.726946E−06  1.523866E−06 A20 1.799973E−01−1.985994E−04  6.181038E−04  7.043271E−07  2.041658E−07 −3.153581E−08

The imaging lens in Example 2 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 4 shows spherical aberration (mm), astigmatism (mm), and distortion(%) of the imaging lens in Example 2. As shown in FIG. 4, eachaberration is corrected excellently.

Example 3

The basic lens data is shown below in Table 3.

TABLE 3 Example 3 Unit mm f = 3.12 Fno = 2.20 ω(°) = 50.0 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 5.32140.3278 1.544 56.44 (νd1)  2* 3.0307 0.2553  3 (Stop) Infinity 0.0554  4*32.6450 0.6592 1.544 56.44 (νd2)  5* −1.6170 0.0250  6* 6.0784 0.35701.671 19.24 (νd3)  7* 3.1607 0.5049  8* −3.8464 1.5210 1.535 55.69 (νd4) 9* −0.9635 0.0200 10* Infinity 0.4300 1.671 19.24 (νd5) 11* Infinity0.0250 12* 9.8472 0.6000 1.639 23.52 (νd6) 13* 1.1590 0.6000 14 Infinity0.2100 1.517 64.20 15 Infinity 0.5095 Image Infinity Plane ConstituentLens Data Lens Start Surface Focal Length 1 1 −13.618 2 4 2.849 3 6−10.324 4 8 2.030 5 10 Infinity 6 12 −2.112 Aspheric Surface Data FirstSecond Fourth Fifth Sixth Seventh Surface Surface Surface SurfaceSurface Surface k 0.000000E+00 0.000000E+00  0.000000E+00  1.746410E+00 0.000000E+00  0.000000E+00 A4 1.334792E−01 3.058968E−01 −1.892492E−02 5.182789E−02 −3.306989E−02 −3.992342E−02 A6 2.295601E−02 −6.711145E−01  7.501182E−01 −1.152750E−01 −3.382294E−01 −1.527517E−01 A8−1.410818E−01  1.164009E+01 −6.402318E+00 −2.316585E−01  2.169433E+00 8.714041E−01 A10 2.098748E−01 −9.453852E+01   3.057669E+01 3.674273E+00 −7.536808E+00 −2.507971E+00 A12 −1.573520E−01 4.506956E+02 −9.212110E+01 −1.401578E+01  1.577996E+01  4.407528E+00 A143.327820E−02 −1.304299E+03   1.813253E+02  2.706647E+01 −2.023681E+01−4.767566E+00 A16 0.000000E+00 2.266727E+03 −2.336367E+02 −2.835258E+01 1.546434E+01  3.078450E+00 A18 0.000000E+00 −2.177051E+03  1.844469E+02  1.484522E+01 −6.444942E+00 −1.087050E+00 A20 0.000000E+008.898162E+02 −6.781784E+01 −2.712445E+00  1.126122E+00  1.612894E−01Eighth Ninth Tenth Eleventh Twelfth Thirteenth Surface Surface SurfaceSurface Surface Surface k  6.068304E+00 −2.169597E+00 −1.000000E+00−1.000000E+00 −1.000000E+00 −2.709576E+00 A4  8.302080E−02 −1.699599E−02−1.159580E−01 −2.334144E−01 −1.490019E−01 −1.738828E−01 A6 −1.763536E−01 5.097816E−02  2.104862E−01  3.798851E−01  9.101145E−02  1.105296E−01 A8 4.380733E−01 −2.538521E−01 −3.485017E−01 −3.582282E−01 −1.077048E−02 4.546267E−02 A10 −6.503338E−01  4.168812E−01  3.764438E−01 2.028115E−01 −1.526325E−02  1.225291E−02 A12  5.065726E−01−3.866123E−01 −3.027884E−01 −7.030909E−02  1.012611E−02 −2.181352E−03A14 −1.140486E−01  2.194066E−01  1.689337E−01  1.493835E−02−3.071605E−03  2.532548E−04 A16 −1.045050E−01 −7.561782E−02−5.893149E−02 −1.901549E−03  5.104658E−04 −1.840207E−05 A18 7.819471E−02  1.454651E−02  1.130000E−02  1.347087E−04 −4.445113E−05 7.573144E−07 A20 −1.586302E−02 −1.194801E−03 −8.999264E−04 4.177995E−06  1.583500E−06 −1.339804E−08

The imaging lens in Example 3 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 6 shows spherical aberration (mm), astigmatism (mm), and distortion(%) of the imaging lens in Example 3. As shown in FIG. 6, eachaberration is corrected excellently.

Example 4

The basic lens data is shown below in Table 4.

TABLE 4 Example 4 Unit mm f = 3.17 Fno = 2.20 ω(°) = 54.5 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 7.36090.3275 1.544 56.44 (νd1)  2* 2.9795 0.4584  3 (Stop) Infinity −0.0313 4* 5.2500 0.6115 1.544 56.44 (νd2)  5* −1.9533 0.0250  6* 8.4074 0.30081.671 19.24 (νd3)  7* 4.1966 0.3366  8* −4.2902 1.5400 1.535 55.69 (νd4) 9* −1.1821 0.0444 10* Infinity 0.4800 1.671 19.24 (νd5) 11* Infinity0.2720 12* Infinity 0.5950 1.639 23.52 (νd6) 13* 1.4963 0.6000 14Infinity 0.2100 1.517 64.20 15 Infinity 0.3300 Image Infinity PlaneConstituent Lens Data Lens Start Surface Focal Length 1 1 −9.443 2 42.695 3 6 −12.861 4 8 2.602 5 10 Infinity 6 12 −2.341 Aspheric SurfaceData First Second Fourth Fifth Sixth Seventh Surface Surface SurfaceSurface Surface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 2.689220E+00  0.000000E+00 0.000000E+00 A4  2.036369E −01 3.910997E−014.112876E−02  5.359177E−02 −1.919698E−02 2.394079E−02 A6 −1.027382E−01 −6.393995E−01  2.127359E−01 −1.608627E−01 −3.414510E−02 −4.542385E−01 A8 −2.890132E−02  7.057725E+00 −2.447244E+00  −1.538920E−01−9.688873E−01 2.388292E+00 A10 3.220201E−01 −4.524275E+01  1.506254E+01 3.692266E+00  6.802519E+00 −7.720657E+00  A12 −6.085406E−01 1.728866E+02 −5.940363E+01  −1.422307E+01 −2.110755E+01 1.624816E+01 A14 5.590523E −01 −3.983390E+02  1.468708E+02  2.692309E+01  3.707169E+01−2.166674E+01  A16 −2.730913E−01  5.473822E+02 −2.199139E+02 −2.814618E+01 −3.834899E+01 1.759052E+01 A18 5.485350E−02 −4.141953E+02 1.799968E+02  1.522085E+01  2.167325E+01 −7.961630E+00  A20 0.000000E+001.325204E+02 −6.132163E +01  −3.195518E+00 −5.113873E+00 1.547077E+00Eighth Ninth Tenth Eleventh Twelfth Thirteenth Surface Surface SurfaceSurface Surface Surface k  6.669268E+00 −2.114392E+00 −1.000000E+00−1.000000E+00 −1.000000E+00 −2.110535E+00 A4  5.123214E−02  1.239788E−01 2.480207E−01  2.495185E−01  1.098070E−02 −2.000549E−01 A6 −4.116041E−02−6.080077E−01 −7.207634E−01 −4.512706E−01 −2.150863E−01  1.094592E−01 A8−3.695194E−01  1.190722E+00  1.133071E+00  4.019315E−01  2.017835E−01−4.361125E−02 A10  2.458662E+00 −1.487220E+00 −1.227196E+00−2.228395E−01 −9.010124E−02  1.283545E−02 A12 −7.079874E+00 1.214813E+00  8.913534E−01  7.959990E−02  2.388321E−02 −2.690946E−03A14  1.115118E+01 −6.435755E−01 −4.238459E−01 −1.818854E−02−3.988826E−03  3.823739E−04 A16 −9.921908E+00  2.112916E−01 1.241752E−01  2.557105E−03  4.146557E−04 −3.453514E−05 A18 4.710847E+00 −3.867998E−02 −2.006101E−02 −2.008775E−04 −2.458286E−05 1.774445E−06 A20 −9.346244E−01  2.992890E−03  1.358931E−03 6.734281E−06  6.352365E−07 −3.927942E−08

The imaging lens in Example 4 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 8 shows spherical aberration (mm), astigmatism (mm), and distortion(%) of the imaging lens in Example 4. As shown in FIG. 8, eachaberration is corrected excellently.

Example 5

The basic lens data is shown below in Table 5.

TABLE 5 Example 5 Unit mm f = 3.08 Fno = 2.20 ω(°) = 54.5 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 9.56050.3275 1.544 56.44 (νd1)  2* 2.7060 0.4816  3 (Stop) Infinity −0.0395 4* 4.5402 0.6090 1.544 56.44 (νd2)  5* −1.8117 0.0250  6* 6.4191 0.30001.671 19.24 (νd3)  7* 3.0881 0.3567  8* −6.0409 1.5400 1.535 55.69 (νd4) 9* −1.1817 0.0200 10* Infinity 0.4853 1.671 19.24 (νd5) 11* Infinity0.2488 12* Infinity 0.5950 1.639 23.52 (νd6) 13* 1.4808 0.6000 14Infinity 0.2100 1.517 64.20 15 Infinity 0.3398 Image Infinity PlaneConstituent Lens Data Lens Start Surface Focal Length 1 1 −7.051 2 42.462 3 6 −9.205 4 8 2.474 5 10 Infinity 6 12 −2.317 Aspheric SurfaceData First Second Fourth Fifth Sixth Seventh Surface Surface SurfaceSurface Surface Surface k 0.000000E+00 0.000000E+00 0.000000E+001.320447E+00  0.000000E+00 0.000000E+00 A4 2.209561E−01 3.874819E−012.428049E−02 4.195938E−02 −1.743464E−04 −7.121319E−05  A6 −1.706732E−01 −4.285290E−01  7.053779E−02 −2.506408E−01  −3.051021E−01 −3.867633E−01 A8 1.955018E−01 6.015485E+00 −3.704243E−01  1.479418E+00  2.233236E+002.373240E+00 A10 −1.775228E−01  −4.368224E+01  −1.437721E−01 −6.225900E+00  −8.149713E+00 −7.286114E +00  A12 9.021894E−021.830564E+02 6.095231E+00 1.704565E+01  1.800497E+01 1.388148E+01 A14−2.504634E−02  −4.540239E+02  −2.164064E+01  −3.092575E+01 −2.486551E+01 −1.661621E+01  A16 0.000000E+00 6.651796E+02 3.439207E+013.491366E+01  2.053522E+01 1.202589E+01 A18 0.000000E+00 −5.319237E+02 −2.613861E+01  −2.209247E+01  −9.144944E+00 −4.790458E+00  A200.000000E+00 1.787623E+02 7.792458E+00 6.062657E+00  1.678877E+008.073419E−01 Eighth Ninth Tenth Eleventh Twelfth Thirteenth SurfaceSurface Surface Surface Surface Surface k  1.153153E+01 −2.049064E+00−1.000000E+00 −1.000000E+00 −1.000000E+00 −2.242993E+00 A4  1.518169E−02 1.705614E−03  7.056451E−02  1.258882E−01 −2.109549E−02 −1.905362E−01 A6−4.519102E−02 −1.796178E−01 −2.965016E−01 −2.719224E−01 −1.746034E−01 1.056281E−01 A8  2.525043E−01  3.937623E−01  5.485044E−01  2.760103E−01 1.818123E−01 −4.242045E−02 A10 −6.962136E−01 −5.014027E−01−6.692067E−01 −1.688628E−01 −8.603057E−02  1.211942E−02 A12 9.056858E−01  3.693652E−01  5.173987E−01  6.451913E−02  2.405381E−02−2.398848E−03 A14 −4.614765E−01 −1.523205E−01 −2.543857E−01−1.541806E−02 −4.250840E−03  3.193623E−04 A16 −8.154853E−02 2.888962E−02  7.537629E−02  2.232341E−03  4.693894E−04 −2.717094E−05A18  1.780138E−01  4.773631E−05 −1.204337E−02 −1.786339E−04−2.961990E−05  1.329166E−06 A20 −5.327916E−02 −5.624092E−04 7.882988E−04  6.050603E−06  8.144665E−07 −2.834407E−08

The imaging lens in Example 5 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 10 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 5. As shown in FIG. 10,each aberration is corrected excellently.

Example 6

The basic lens data is shown below in Table 6.

TABLE 6 Example 6 Unit mm f = 3.08 Fno = 2.20 ω(°) = 54.5 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 3.92300.3275 1.544 55.93 (νd1)  2* 2.1568 0.4433  3 (Stop) Infinity 0.0359  4*16.6400 0.7897 1.535 55.69 (νd2)  5* −1.3834 0.0250  6* 5.5562 0.31571.671 19.24 (νd3)  7* 2.5544 0.5677  8* −5.0081 1.1892 1.544 55.93 (νd4) 9* −1.3069 0.0361 10* Infinity 0.4000 1.671 19.24 (νd5) 11* Infinity0.1591 12* 3.3120 0.5950 1.614 25.59 (νd6) 13* 1.0641 0.6000 14 Infinity0.2100 1.517 64.20 15 Infinity 0.4056 Image Infinity Plane ConstituentLens Data Lens Start Surface Focal Length 1 1 −9.417 2 4 2.425 3 6−7.360 4 8 2.918 5 10 Infinity 6 12 −2.839 Aspheric Surface Data FirstSecond Fourth Fifth Sixth Seventh Surface Surface Surface SurfaceSurface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 9.156547E−01 0.000000E+00  0.000000E+00 A4 1.481335E−01 2.326361E−01 −1.631833E−02 1.211178E−01 −1.036758E−01 −1.835762E−01 A6 −7.241478E−02  6.221543E−014.172064E−02 −3.332400E−01   2.645300E−01  3.849702E−01 A8 1.407488E−01−5.292667E+00  −4.851245E−01  1.542467E+00 −1.262377E+00 −1.062796E+00A10 −2.392969E−01  2.930250E+01 4.728804E−01 −6.258822E+00  3.969133E+00  2.301117E+00 A12 2.567578E−01 −1.002461E+02  3.766803E+001.750401E+01 −8.007049E+00 −3.424962E+00 A14 −1.534367E−01  2.166304E+02−1.892487E+01  −3.159589E+01   1.007646E+01  3.296866E+00 A163.389416E−02 −2.851396E+02  3.742673E+01 3.482864E+01 −7.693730E+00−1.958574E+00 A18 0.000000E+00 2.086787E+02 −3.719651E+01 −2.123677E+01   3.264791E+00  6.518552E−01 A20 0.000000E+00−6.563896E+01  1.479133E+01 5.492549E+00 −5.889189E−01 −9.282695E−02Eighth Ninth Tenth Eleventh Twelfth Thirteenth Surface Surface SurfaceSurface Surface Surface k 1.140197E+01 −3.249238E+00 0.000000E+00 0.000000E+00 −3.096007E+01 −4.636422E+00 A4 1.311887E−02 −1.279772E−013.884332E−02  1.768887E−01 −5.316492E−02 −1.132005E−01 A6 1.176134E−01 2.173463E−01 8.130358E−02 −2.380775E−01 −1.199028E−01  4.789622E−02 A8−2.970809E−01  −2.781895E−01 -3.207436E−01   1.325203E−01  1.231478E−01−1.193621E−02 A10 4.827510E−01  1.680328E−01 3.998165E−01 −3.439833E−02−5.478334E−02  1.261587E−03 A12 −5.029935E−01  −2.024072E−04−3.008751E−01  −2.621375E−04  1.418181E−02  1.410890E−04 A143.434360E−01 −6.125502E−02 1.484473E−01  2.638525E−03 −2.277111E−03−6.328158E−05 A16 −1.469118E−01   3.626078E−02 −4.741905E−02 −7.001171E−04  2.243364E−04  8.388443E−06 A18 3.539673E−02 −8.868151E−038.789073E−03  7.931953E−05 −1.247082E−05 −5.171248E−07 A20−3.639312E−03   8.070907E−04 −7.022709E−04  −3.467365E−06  3.004226E−07 1.250321E−08

The imaging lens in Example 6 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 12 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 6. As shown in FIG. 12,each aberration is corrected excellently.

Example 7

The basic lens data is shown below in Table 7.

TABLE 7 Example 7 Unit mm f = 3.08 Fno = 2.20 ω(°) = 54.5 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 4.39070.3275 1.544 55.93 (νd1)  2* 2.1710 0.4263  3 (Stop) Infinity 0.0451  4*20.0574 0.6538 1.544 55.93 (νd2)  5* −1.6757 0.0302  6* 3.5011 0.30001.671 19.24 (νd3)  7* 1.9762 0.2669  8* 20.0378 1.5213 1.535 55.69 (νd4) 9* −1.5601 0.2197 10* Infinity 0.4098 1.671 19.24 (νd5) 11* Infinity0.1508 12* 3.9826 0.5800 1.614 25.59 (νd6) 13* 1.1894 0.6000 14 Infinity0.2100 1.517 64.20 15 Infinity 0.3581 Image Infinity Plane ConstituentLens Data Lens Start Surface Focal Length 1 1 −8.323 2 4 2.872 3 6−7.345 4 8 2.774 5 10 Infinity 6 12 −2.998 Aspheric Surface Data FirstSecond Fourth Fifth Sixth Seventh Surface Surface Surface SurfaceSurface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 1.267632E+00 0.000000E+00  0.000000E+00 A4 2.139030E−01 3.395059E−01 2.684822E−027.401817E−02 −1.829230E−01 −2.195474E−01 A6 −3.079895E−01 −7.970117E−02  −4.257243E−02  −2.026275E−01   5.131342E−01  2.642968E−01A8 1.278742E+00 2.917661E+00 −1.022467E−01  1.250633E+00 −2.191481E+00−5.144172E−01 A10 −3.889680E+00  −2.721355E+01  2.411828E−01−6.096812E+00   7.205521E+00  1.193623E+00 A12 7.713419E+00 1.364405E+021.126554E+00 1.737294E+01 −1.581965E+01 −2.188386E+00 A14 −9.740196E+00 −3.921863E+02  −1.259215E+01  −3.156932E+01   2.168884E+01  2.504040E+00A16 7.543835E+00 6.575863E+02 3.744105E+01 3.495320E+01 −1.793471E+01−1.690061E+00 A18 −3.276096E+00  −5.973441E+02  −5.119157E+01 −2.129872E+01   8.185701E+00  6.159588E−01 A20 6.084028E−01 2.251713E+022.706209E+01 5.387432E+00 −1.576352E+00 −9.282166E−02 Eighth Ninth TenthEleventh Twelfth Thirteenth Surface Surface Surface Surface SurfaceSurface k 0.000000E+00 −4.190637E+00 0.000000E+00  0.000000E+00−2.196350E+01 −4.776088E+00 A4 5.684567E−02 −5.383961E−02 1.328738E−01 2.405141E−01 −1.005849E−01 −1.421309E−01 A6 −2.492397E−03  4.198172E−02 −2.047555E−01  −3.879665E−01 −1.201512E−01  6.732585E−02A8 −1.008036E−01  −1.061770E−01 3.416908E−02  2.565473E−01  1.575916E−01−1.622959E−02 A10 2.123322E−01  1.646341E−01 1.079897E−01 −9.479158E−02−7.847617E−02  1.006612E−03 A12 −1.906889E−01  −1.306256E−01−1.473557E−01   1.977862E−02  2.195509E−02  4.243740E−04 A145.541955E−02  5.577930E−02 1.046204E−01 −1.960759E−03 −3.738695E−03−1.175789E−04 A16 2.967504E−02 −1.117136E−02 −4.581053E−02 −3.991287E−06  3.856542E−04  1.329198E−05 A18 −2.572142E−02  4.548390E−04 1.123133E−02  1.710344E−05 −2.222310E−05 −7.320897E−07 A205.218491E−03  9.280060E−05 −1.142842E−03  −9.956979E−07  5.503915E−07 1.610650E−08

The imaging lens in Example 7 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 14 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 7. As shown in FIG. 14,each aberration is corrected excellently.

Example 8

The basic lens data is shown below in Table 8.

TABLE 8 Example 8 Unit mm f = 3.08 Fno = 2.20 ω(°) = 54.5 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 4.50550.3275 1.544 55.93 (νd1)  2* 2.3142 0.4175  3 (Stop) Infinity 0.0451  4*−1625.4480 0.6417 1.544 55.93 (νd2)  5* −1.6118 0.0471  6* 3.5474 0.30001.671 19.24 (νd3)  7* 2.0059 0.2647  8* 20.0378 1.5370 1.535 55.69 (νd4) 9* −1.5588 0.2177 10* Infinity 0.4104 1.671 19.24 (νd5) 11* Infinity0.1428 12* 3.7875 0.5800 1.614 25.59 (νd6) 13* 1.1693 0.6000 14 Infinity0.2100 1.517 64.20 15 Infinity 0.3584 Image Infinity Plane ConstituentLens Data Lens Start Surface Focal Length 1 1 −9.228 2 4 2.964 3 6−7.465 4 8 2.773 5 10 Infinity 6 12 −3.007 Aspheric Surface Data FirstSecond Fourth Fifth Sixth Seventh Surface Surface Surface SurfaceSurface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 1.232934E+00 0.000000E+00  0.000000E+00 A4 2.047733E−01 3.238716E−01 1.805472E−027.222558E−02 −1.655516E−01 −2.092608E−01 A6 −2.116709E−01  2.453314E−01−5.845174E−02  −2.037745E−01   3.568758E−01  2.083411E−01 A87.207254E−01 −1.351057E+00  −9.495710E−02  1.256524E+00 −1.437260E+00−3.096317E−01 A10 −1.959461E+00  2.999893E+00 2.525073E−01−6.088693E+00   4.696106E+00  5.722463E−01 A12 3.677182E+00 9.824888E+001.112987E+00 1.737433E+01 −1.037823E+01 −9.702865E−01 A14 −4.553907E+00 −6.835992E+01  −1.272507E+01  −3.157774E+01   1.429100E+01  1.052234E+00A16 3.546760E+00 1.599587E+02 3.723863E+01 3.494834E+01 −1.183389E+01−6.663575E−01 A18 −1.579975E+00  −1.741230E+02  −5.105478E+01 −2.129842E+01   5.394578E+00  2.227860E−01 A20 3.029676E−01 7.189177E+012.741126E+01 5.374564E+00 −1.034339E+00 −2.954240E−02 Eighth Ninth TenthEleventh Twelfth Thirteenth Surface Surface Surface Surface SurfaceSurface k 0.000000E+00  4.157407E+00 0.000000E+00  0.000000E+00−2.136723E+01 −4.676720E+00 A4 4.660361E−02 −5.618232E−02 1.328605E−01 2.389705E−01 −1.017790E−01 −1.434320E−01 A6 7.187160E−02  5.495606E−02−1.929751E−01  −3.813978E−01 −1.184331E−01  6.883802E−02 A8−3.466656E−01  −1.392649E−01 1.838768E−03  2.466878E−01  1.565516E−01−1.692185E−02 A10 7.165061E−01  2.122321E−01 1.580826E−01 −8.722069E−02−7.812172E−02  1.159647E−03 A12 −8.588086E−01  −1.723890E−01−1.945214E−01   1.643002E−02  2.187743E−02  4.161284E−04 A146.254830E−01  7.920054E−02 1.317885E−01 −1.070797E−03 −3.726790E−03−1.209302E−04 A16 −2.725170E−01  −1.945869E−02 −5.488294E−02 −1.446807E−04  3.843511E−04  1.405625E−05 A18 6.485538E−02  2.133437E−031.279521E−02  2.932320E−05 −2.213180E−05 −7.963498E−07 A20−6.486042E−03  −5.260105E−05 −1.246567E−03  −1.445238E−06  5.474442E−07 1.809117E−08

The imaging lens in Example 8 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 16 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 8. As shown in FIG. 16,each aberration is corrected excellently.

Example 9

The basic lens data is shown below in Table 9.

TABLE 9 Example 9 Unit mm f = 3.08 Fno = 2.20 ω(°) = 54.5 h = 3.71 TTL =6.03 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 6.33600.3275 1.544 55.93 (νd1)  2* 2.5843 0.4227  3 (Stop) Infinity 0.0121  4*21.7787 0.7939 1.544 55.93 (νd2)  5* −1.6468 0.0250  6* 3.9127 0.34821.671 19.24 (νd3)  7* 2.0789 0.2602  8* 40.7097 1.2728 1.535 55.69 (νd4) 9* −1.7494 0.3701 10* Infinity 0.4000 1.671 19.24 (νd5) 11* Infinity0.1465 12* 2.6098 0.5500 1.614 25.59 (νd6) 13* 1.0997 0.6000 14 Infinity0.2100 1.517 64.20 15 Infinity 0.3610 Image Infinity Plane ConstituentLens Data Lens Start Surface Focal Length 1 1 −8.273 2 4 2.847 3 6−7.158 4 8 3.169 5 10 Infinity 6 12 −3.592 Aspheric Surface Data FirstSecond Fourth Fifth Sixth Seventh Surface Surface Surface SurfaceSurface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 8.985787E−01 0.000000E+00  0.000000E+00 A4 2.263271E−01 4.448919E−01 1.136454E−019.727224E−02 −1.178326E−01 −1.780342E−01 A6 −2.767123E−01 −1.320721E+00  −1.394171E+00  −3.382755E−01   2.442416E−01  2.284520E−01A8 9.084906E−01 1.335635E+01 1.650331E+01 2.467157E+00 −1.134331E+00−5.881744E−01 A10 −2.351895E+00  −7.984419E+01  −1.152783E+02 −1.236271E+01   3.613849E+00  1.340995E+00 A12 4.162629E+00 3.041126E+024.994143E+02 3.765240E+01 −7.662871E+00 −2.199002E+00 A14 −4.810531E+00 −7.272932E+02  −1.355261E+03  −7.048870E+01   1.049749E+01  2.364247E+00A16 3.459373E+00 1.062919E+03 2.244113E+03 7.898768E+01 −9.030823E+00−1.595205E+00 A18 −1.406923E+00  −8.647498E+02  −2.073013E+03 −4.841743E+01   4.460627E+00  6.126796E−01 A20 2.453365E−01 2.999766E+028.192444E+02 1.252079E+01 −9.602614E−01 −1.017990E−01 Eighth Ninth TenthEleventh Twelfth Thirteenth Surface Surface Surface Surface SurfaceSurface k 0.000000E+00 −5.346743E+00 0.000000E+00 0.000000E+00−1.901991E+01 4.655415E+00 A4 6.303981E−02 −7.991110E−02 1.218544E−012.196877E−01 −1.060698E−01 −1.447777E−01  A6 6.796465E−03  3.184989E−02−2.562160E−01  −4.520592E−01  −1.410682E−01 7.462577E−02 A8−9.387206E−02   4.229424E−02 1.737253E−01 4.257505E−01  1.797850E−01−2.497768E−02  A10 2.177692E−01 −1.216937E−01 2.080949E−02−2.406452E−01  −8.910943E−02 5.083331E−03 A12 −3.002958E−01  1.709494E−01 −1.730763E−01  8.453835E−02  2.503559E−02 −5.371094E−04 A14 2.765088E−01 −1.425242E−01 1.708664E−01 −1.852466E−02  −4.310546E−037.027931E−06 A16 −1.658351E−01   7.053075E−02 −8.615266E−02 2.465545E−03  4.519702E−04 4.597494E−06 A18 5.726790E−02 −1.859187E−022.246591E−02 −1.825586E−04  −2.658053E−05 −4.493669E−07  A20−8.556668E−03   1.975500E−03 −2.349532E−03  5.767432E−06  6.737817E−071.359223E−08

The imaging lens in Example 9 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 18 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 9. As shown in FIG. 18,each aberration is corrected excellently.

Example 10

The basic lens data is shown below in Table 10.

TABLE 10 Example 10 Unit mm f = 2.71 Fno = 2.20 ω(°) = 56.2 h = 3.71 TTL= 5.60 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 8.64220.3742 1.535 55.69 (νd1)  2* 2.3547 0.3991  3 (Stop) Infinity 0.0100  4*6.7524 0.6815 1.544 55.93 (νd2)  5* −1.9060 0.0217  6* −500.0000 0.20001.671 19.24 (νd3)  7* 4.6984 0.1184  8* −10.3482 0.7679 1.535 55.69(νd4)  9* −1.5848 0.5045 10* Infinity 0.6953 1.535 55.69 (νd5) 11*Infinity 0.1782 12* 1.7971 0.6644 1.614 25.59 (νd6) 13* 1.0555 0.5500 14Infinity 0.2100 1.517 64.20 15 Infinity 0.3008 Image Infinity PlaneConstituent Lens Data Lens Start Surface Focal Length 1 1 −6.180 2 42.809 3 6 −6.938 4 8 3.396 5 10 Infinity 6 12 −6.318 Aspheric SurfaceData First Second Fourth Fifth Sixth Seventh Surface Surface SurfaceSurface Surface Surface k 0.000000E+00 0.000000E+00 0.000000E+00 3.257950E+00  0.000000E+00  0.000000E+00 A4 2.509834E−01 5.045987E−017.231745E−02 −1.503137E−02 −1.961195E−01 −1.491307E−01 A6 −2.786727E−01 −1.104773E+00  −1.467664E+00  −3.905839E−01  1.693132E−01  2.209796E−01A8 8.961541E−01 1.244789E+01 1.644351E+01  2.382622E+00 −1.159287E+00−6.277157E−01 A10 −2.321756E+00  −7.793297E+01  −1.155116E+02 −1.226845E+01  3.666129E+00  1.387827E+00 A12 4.158331E+00 3.040985E+024.994146E+02  3.764756E+01 −7.740929E+00 −2.199300E+00 A14−4.801424E+00  −7.272931E+02  −1.355261E+03  −7.048880E+01  1.058094E+01 2.357787E+00 A16 3.458351E+00 1.062919E+03 2.244113E+03  7.898768E+01−9.030675E+00 −1.605569E+00 A18 −1.407159E+00  −8.647498E+02 −2.073013E+03  −4.841743E+01  4.460636E+00  6.126507E−01 A202.453139E−01 2.999766E+02 8.192444E+02  1.252079E+01 −9.602600E−01−1.018010E−01 Eighth Ninth Tenth Eleventh Twelfth Thirteenth SurfaceSurface Surface Surface Surface Surface k 0.000000E+00 4.767275E+000.000000E+00 0.000000E+00  0.000000E+00 −2.542248E+00  A4 4.888412E−02−1.193719E−01  8.723967E−02 1.313210E−01 −1.888548E−01 −1.585787E−01  A64.691617E−03 1.429285E−02 −2.629688E−01  −4.401547E−01  −1.579355E−017.628326E−02 A8 −6.143961E−02  4.777043E−02 1.818238E−01 4.261467E−01 1.617216E−01 −2.508817E−02  A10 2.155837E−01 −1.103624E−01 9.752575E−03 −2.472234E−01  −8.411183E−02 5.047677E−03 A12−3.075183E−01  1.722451E−01 −1.702128E−01  8.565372E−02  2.434023E−02−5.281190E−04  A14 2.765436E−01 −1.423056E−01  1.716893E−01−1.808581E−02  −3.810019E−03 6.847121E−06 A16 −1.547868E−01 7.058545E−02 −8.698844E−02  2.418369E−03  5.227712E−04 4.565150E−06 A183.912541E−02 −1.764496E−02  2.222286E−02 −1.886686E−04  −8.456335E−054.582229E−07 A20 0.000000E+00 2.097791E−03 −2.324314E−03  0.000000E+00 0.000000E+00 1.441375E−08

The imaging lens in Example 10 satisfies conditional expressions (1) to(18) as shown in Table 12.

FIG. 20 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 10. As shown in FIG. 20,each aberration is corrected excellently.

Example 11

The basic lens data is shown below in Table 11.

TABLE 11 Example 11 Unit mm f = 2.76 Fno = 2.20 ω(°) = 55.7 h = 3.71 TTL= 5.61 Surface Data i r d Nd νd (Object) Infinity Infinity  1* 5.09820.3821 1.535 55.69 (νd1)  2* 1.8529 0.4423  3 (Stop) Infinity 0.0100  4*5.3592 0.7209 1.544 55.93 (νd2)  5* −1.8741 0.0440  6* 400.0000 0.20001.671 19.24 (νd3)  7* 3.8952 0.1113  8* −17.8032 0.7889 1.535 55.69(νd4)  9* −1.6137 0.5327 10* Infinity 0.3703 1.535 55.69 (νd5) 11*Infinity 0.1520 12* 1.7958 0.6474 1.535 55.69 (νd6) 13* 1.1001 0.5500 14Infinity 0.2100 1.517 64.20 15 Infinity 0.5158 Image Infinity PlaneConstituent Lens Data Lens Start Surface Focal Length 1 1 −5.675 2 42.644 3 6 −5.750 4 8 3.263 5 10 Infinity 6 12 −7.858 Aspheric SurfaceData First Second Fourth Fifth Sixth Seventh Surface Surface SurfaceSurface Surface Surface k 0.000000E+00 0.000000E+00 0.000000E+003.094917E+00  0.000000E+00  0.000000E+00 A4 2.361808E−01 4.940023E−016.500759E−02 −2.164381E−02  −1.998467E−01 −1.521684E−01 A6−2.726535E−01  −1.082188E+00  −1.464787E+00  −3.952532E−01  1.627495E−01  2.180769E−01 A8 9.016111E−01 1.244037E+01 1.647071E+012.400197E+00 −1.174365E+00 −6.312939E−01 A10 −2.326265E+00 −7.780677E+01  −1.156263E+02  −1.228609E+01   3.668935E+00  1.389003E+00A12 4.158331E+00 3.040985E+02 4.994146E+02 3.764756E+01 −7.740929E+00−2.199300E+00 A14 −4.801424E+00  −7.272931E+02  −1.355261E+03 −7.048880E+01   1.058094E+01  2.357787E+00 A16 3.458351E+00 1.062919E+032.244113E+03 7.898768E+01 −9.030675E+00 −1.605569E+00 A18 −1.407159E+00 −8.647498E+02  −2.073013E+03  4.841743E+01  4.460636E+00  6.126507E−01A20 2.453139E−01 2.999766E+02 8.192444E+02 1.252079E+01 −9.602600E−01−1.018010E−01 Eighth Ninth Tenth Eleventh Twelfth Thirteenth SurfaceSurface Surface Surface Surface Surface k 0.000000E+00 4.055519E+000.000000E+00 0.000000E+00  0.000000E+00 −2.032380E+00  A4 4.621200E−02−1.212919E−01  4.448397E−02 1.232337E−01 −1.731471E−01 −1.707827E−01  A6−2.226054E−04 1.568926E−02 −2.742867E−01  4.408271E−01 −1.439280E−017.951514E−02 A8 −6.073701E−02 4.924524E−02 1.891211E−01 4.280397E−01 1.605532E−01 −2.560541E−02  A10 2.188052E−01 −1.091270E−01 9.090069E−03 −2.470409E−01  −8.472610E−02 5.065216E−03 A12 −3.082898E−011.722380E−01 −1.701494E−01  8.569488E−02  2.418460E−02 −5.268945E−04 A14 2.753918E−01 −1.423685E−01  1.711143E−01 −1.808036E−02 −3.821598E−03 7.101163E−06 A16 −1.547867E−01 7.039602E−02 −8.698800E−02 2.417715E−03  5.230131E−04 4.548558E−06 A18 3.912548E−02 −1.764497E−02 2.222307E−02 4.891354E−04 −8.137837E−05 4.610907E−07 A20 0.000000E+002.097785E−03 −2.324190E−03  0.000000E+00  0.000000E+00 1.415830E−08

The imaging lens in Example 11 satisfies conditional expressions (1) to(6), and (8) to (18) as shown in Table 12.

FIG. 22 shows spherical aberration (mm), astigmatism (mm), anddistortion (%) of the imaging lens in Example 11. As shown in FIG. 22,each aberration is corrected excellently.

In table 12, values of conditional expressions (1) to (18) related toExamples 1 to 11 are shown.

TABLE 12 Conditional Expressions Example 1 Example 2 Example 3 Example 4Example 5 Example 6  (1) (T1/f1) × 100 −3.94 −4.22 −2.28 −4.52 −6.27−5.09  (2) T2/T3 0.07 0.07 0.05 0.07 0.07 0.04  (3) f6/D6 −3.82 −3.84−3.52 −3.93 −3.89 4.77  (4) r2/r4 −1.81 −1.78 −1.87 −1.53 −1.49 −1.56 (5) r1/f 3.28 2.52 1.71 2.32 3.11 1.27  (6) r12/D6 2.37 2.46 1.93 2.512.49 1.79  (7) νd6 23.52 23.52 23.52 23.52 23.52 25.59  (8) (D1/f1) ×100 −3.04 −3.16 −2.41 −3.47 −4.64 −3.48  (9) D2/D3 2.19 2.08 1.85 2.032.03 2.50 (10) f4/f 0.78 0.79 0.65 0.82 0.80 0.95 (11) f1/f4 −4.42 −4.22−6.71 −3.63 −2.85 −3.23 (12) f1/f6 4.74 4.53 6.45 4.03 3.04 3.32 (13)|r3|/r4 −2.64 −3.54 −20.19 −2.69 −2.51 −12.03 (14) r2/r4/r6 −0.43 −0.49−0.59 −0.36 −0.48 −0.61 (15) r2/T2 145.83 128.07 121.23 119.18 108.2486.27 (16) r4/f −0.65 −0.58 −0.52 −0.62 −0.59 −0.45 (17) |r7|/f 1.251.24 1.23 1.35 1.96 1.63 (18) r8/f −0.36 −0.36 −0.31 −0.37 −0.38 −0.42Conditional Expressions Example 7 Example 8 Example 9 Example 10 Example11  (1) (T1/f1) × 100 −5.66 −5.01 −5.26 −6.62 −7.97  (2) T2/T3 0.11 0.180.10 0.18 0.40  (3) f6/D6 −5.17 −5.18 −6.53 −9.51 −12.14  (4) r2/r4−1.30 −1.44 −1.57 −1.24 −0.99  (5) r1/f 1.43 1.46 2.06 3.19 1.84  (6)r12/D6 2.05 2.02 2.00 1.59 1.70  (7) νd6 25.59 25.59 25.59 25.59 55.69 (8) (D1/f1) × 100 −3.93 −3.55 −3.96 −6.05 −6.73  (9) D2/D3 2.18 2.142.28 3.41 3.60 (10) f4/f 0.90 0.90 1.03 1.25 1.18 (11) f1/f4 −3.00 −3.33−2.61 −1.82 −1.74 (12) f1/f6 2.78 3.07 2.30 0.98 0.72 (13) |r3|/r4−11.97 −1008.49 −13.22 −3.54 −2.86 (14) r2/r4/r6 −0.66 −0.72 −0.75 −0.26−0.25 (15) r2/T2 71.77 49.14 103.37 108.60 42.12 (16) r4/f −0.54 −0.52−0.53 −0.70 −0.68 (17) |r7|/f 6.50 6.50 13.21 3.81 6.44 (18) r8/f −0.51−0.51 −0.57 −0.58 −0.58

When the imaging lens according to the present invention is adopted to aproduct with the camera function, there is realized contribution to thelow profile and the low F-number of the camera and also high performancethereof.

DESCRIPTION OF REFERENCE NUMERALS

-   ST: aperture stop-   L1: first lens-   L2: second lens-   L3: third lens-   L4: fourth lens-   L5: fifth lens-   L6: sixth lens-   ih: maximum image height-   IR: filter-   IMG: imaging plane

What is claimed is:
 1. An imaging lens comprising, in order from anobject side to an image side, a first lens with negative refractivepower having an object-side surface being convex in a paraxial region, asecond lens with positive refractive power in a paraxial region, a thirdlens with negative refractive power in a paraxial region, a fourth lenswith positive refractive power in a paraxial region, a fifth lens havinga flat object-side surface and a flat image-side surface that areaspheric, and a sixth lens with negative refractive power having animage-side surface being concave in a paraxial region.
 2. The imaginglens according to claim 1, wherein an image-side surface of said firstlens is concave in a paraxial region.
 3. The imaging lens according toclaim 1, wherein an image-side surface of said second lens is convex ina paraxial region.
 4. The imaging lens according to claim 1, wherein animage-side surface of said fourth lens is convex in a paraxial region.5. The imaging lens according to claim 1, wherein the followingconditional expression (1) is satisfied:−9.55<(T1/f1)×100<−1.00  (1) where T1: a distance along the optical axisfrom an image-side surface of the first lens to an object-side surfaceof the second lens, and f1: a focal length of the first lens.
 6. Theimaging lens according to claim 1, wherein the following conditionalexpression (2) is satisfied:0.02<T2/T3<0.60  (2) where T2: a distance along the optical axis from animage-side surface of the second lens to an object-side surface of thethird lens, and T3: a distance along the optical axis from an image-sidesurface of the third lens to an object-side surface of the fourth lens.7. The imaging lens according to claim 1, wherein the followingconditional expression (3) is satisfied:−15.50<f6/D6<−1.50  (3) where f6: a focal length of the sixth lens, andD6: a thickness along the optical axis of the sixth lens.
 8. The imaginglens according to claim 1, wherein the following conditional expression(4) is satisfied:−2.45<r2/r4<−0.45  (4) where r2: a paraxial curvature radius of animage-side surface of the first lens, and r4: a paraxial curvatureradius of an image-side surface of the second lens.
 9. The imaging lensaccording to claim 1, wherein the following conditional expression (5)is satisfied:0.65<r1/f<4.00  (5) where r1: a paraxial curvature radius of anobject-side surface of the first lens, and f: a focal length of theoverall optical system of the imaging lens.
 10. The imaging lensaccording to claim 1, wherein the following conditional expression (6)is satisfied:0.80<r12/D6<3.00  (6) where r12: a paraxial curvature radius of animage-side surface of the sixth lens, and D6: a thickness along theoptical axis of the sixth lens.